Calfee Refresh Follow-Up: Rear Derailleurs

gsgIt’s all about capacity, and the numbers are the numbers.

I’m not sure why I decided to ignore the specs on the Shimano RD 6700 Ultegra rear derailleur as they were pretty clear: 39T capacity w/28T max sprocket.  But, no, I bought into several accounts of using this derailleur on 34t cassettes, etc. and rolled the dice.

Yeah, well…  Once it was installed it was pretty clear that the cage just wasn’t long enough to support the 44T difference on our Calfee or the 32T rear sprocket.  It was close, very close, but close doesn’t cut it when your derailleur’s upper idler pulley is making contact with the 32t sprocket teeth in the ‘alpine gear’ with the B-screw all the way out.

T20151004_122747hankfully, the Ultegra 6700 10-speed shifters and 10-speed cassette work just fine with my late 1990’s vintage Shimano XTR / RD-M950 8 speed derailleur.  No, its specs also come up a little short on capacity, but since it supports a 32T rear sprocket it keeps the idler pulley and 32t rear sprocket separated. Oh, and even though it was designed for an 8 speed system, the derailleur geometry seems to work just fine with the 10 speed cassette spacing and Shimano Ultegra 6700 shifters, in the stand and on the road.

So, the Ultegra is headed back to the wonderful eBay seller who had made it available to us for a refund and we’ll just use the vintage XTR M950 rear derailleur until any problems develop.

Looking forward to getting some tandem time this coming weekend as we’ll be off the pedal bikes for the next two weekends, perhaps even the next three.

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About TG

I've been around a bit and done a few things, have a couple kids and a few grandkids. I tend to be curmudgeonly, matter-of-fact and not predisposed to self-serving chit-chat. Thankfully, my wife's as nice as can be otherwise we'd have no friends. My interests are somewhat eclectic, but whose aren't?
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5 Responses to Calfee Refresh Follow-Up: Rear Derailleurs

  1. Bruce Brown says:

    I have been following your change in shifters on your Calfee. We have been running a Campy long cage rear with 10 speed shifters for years on our CoMotion. I recently changed out the 11-28 cassette and went with a 11-32. It works fine with the 32 even though Campy says it wouldn’t. It is told that Campy only lists their max cog that is alignment with their cassette offerings. Since they don’t offer a 32, their max is a 29. I am careful about combinations as always to avoid cross over with the robust 54-44-34 front exceeding capacity. I found the wider range decreases the numbers of shifts I need to make compared to the 11-28. I’ve been riding Campy since the late 70’s and only strayed once with Shimano 8 speed STI.
    Thank you for your continued writings and good luck with your conversion!

    • TG says:

      Thanks for the feedback Bruce.

      I did well with the Campy for many years, but pushed the limits of the Record and Chorus Long Cage rear derailleurs when we moved to the Calfee in 2008. Initially, the 30t front with the 28t rear worked well and without any interference. However, once we switched to a 32t rear sprocket the idler pulley and 32t cog would grind on each other. That’s what finally led me to using the SRAM off-road derailleurs with their very long cages. As noted, while I could have replaced the worn-out G-spring in the Campy Record rear derailleur, I opted to do some experimentation and shake things up a bit by switching over to the Ultegra shifters w/Shimano XTR rear derailleur. Trust me, I’ve kept my Campy parts and will likely overhaul the shifters in the event that I just can’t adapt to the Ultregras for the long haul.

  2. cbratina says:

    There are two different dropout hanger to axle distances commonly used. I found that the exact same drivetrain worked great on a Litespeed Appalachian cross bike but not on a custom DeSalvo dirt road bike. After a month of pulling my hair out trying different components, I found the dropout distances were very different.

    • TG says:

      Great point…

      There are a lot of different dimensions and gearing choices that will ultimately determine what works and what doesn’t work. As a long-time Campy user our challenge has always been finding solutions that support alpine gearing for the very steep 18% – 20% grades we sometimes encounter here in North Georgia, Eastern Tennessee and Western North Carolina. As much as I wish we could get by with Campy’s largest, 29t sprocket in back, pushing close to our 60’s we’ve come to appreciate having that Shimano-spaced 32t back there. Coupled with a 30t alpine ring up front creates challenges that require adapters for non-Campy rear derailleurs.

  3. Joel says:

    I switched to a SRAM WiFli RD and use it with 12-32 cassette. It works pretty well with my Campy Centaur shifters although not a perfect ratio. The SRAM RD looks nicer and seems better quality than Shimano.

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